In the bulk material shipping industry, where plastic bags in totes, such as plastic totes, are used to ship quantities of liquids, pastes, granular materials, powders, and other flowable and semi-flowable bulk materials, substantial quantities of the bulk material can be left in the bag when the bag has been nearly completely evacuated. This is true even where pumps are connected to the drain ports of the bags, and is especially true of more flow-resistant bulk materials, such as drywall paste and mayonnaise. This problem with bulk material shipper bags is created when the bag is evacuated and collapses, which leaves folds of bag material in the tote. When the excess folds are on the bottom near the drain, they can be sucked against the drain port, stalling the pump.
To reduce the amount of bulk material wasted by being left in the bag, prior inventors have tried several approaches. One approach is to incline the bottom of the bag toward the drain port by tilting part or all of the base of the shipping container or even tilting the entire shipping container, plastic tote and all. This approach can be complicated and inefficient since it requires mechanical apparatus to tilt the container if it is not done manually. Additionally, since this approach does little, if anything, to hold the bag in place within the rigid container, the bag can slide when the bottom of the container is tilted. The sliding bag can block the drain port, which prevents removal of further bulk material from the bag and can cause pump stalling.
Another approach is to use a special structure in the bag or in the rigid container to squeeze the residual contents out of the bag. In the case of special structures in the bag, one arrangement stiffens the bag near the drain port using battens or other stiffeners that add to the cost of the bag. Another arrangement adds a special chamber to the bag that can be filled with pressurized air to squeeze the contents from the primary chamber. This arrangement requires the addition of material to the bag solely for the purpose of squeezing the contents of the primary chamber, which increases cost and complexity of manufacture and is inelegant. Additionally, there is no way to prevent pump stalling by excess folds of bag material from blocking the drain port at low bulk material levels. Squeezing the bulk material from the bag in this manner also requires relatively high pressure. To resist the high pressure, reinforced bag material or external pressure-resistant containers must be used that are more expensive than conventional bags and containers.
In the case of special structures in the rigid container, prior inventors have used piston arrangements, rollers, and other external squeezing arrangements. A more passive special rigid container is the pressure-resistant container discussed above. These clearly add significant cost and complexity to the rigid container. Though blockage of the drain port by excess bag material is not as prevalent in these arrangements as it is in arrangements using inflatable chambers, neither is there a way to prevent such blockage.
Another technique for reducing blockage of the drain port is to leave the plunging arrow used to puncture the shipper bag through the drain port extended into the bag. When the bag is evacuated, the plunging arrow presents itself as an obstacle to blockage of the drain port. This delays or reduces the amount of blockage, but a significant amount of bulk material is still left in the bag.
Another prior art device, known as an antivacuum device, can be attached to the drain port to reduce and/or delay blockage of the drain port. The antivacuum device is a cylinder that extends into the bag interior from the drain fitment. A plurality of holes are cut in the sides of the cylinder so that bulk material can flow through the holes if the main opening of the cylinder is blocked by folds of bag material. While this does reduce or delay blockage of the drain port and the amount of wasted bulk material, a significant amount of bulk material is left behind. Additionally, the antivacuum device undesirably increases the cost and complexity of bag manufacture.
A disadvantage of all prior attempts to enhance evacuation of shipper bags and reduce wasted bulk material is that they generally require human intervention during evacuation. Prior arrangements cannot simply be hooked up and allowed to operate until all bulk material that can be has been evacuated. Rather, a human attendant must do something during evacuation to initiate the evacuation enhancement.
With the disadvantages of the prior art, there is a need for a simple, inexpensive, and elegant way to enhance shipper bag evacuation. There is also a need for a liquid shipper arrangement that avoids or at least significantly delays sucking of excess bag material against the drain port of the bag. An enhanced-evacuation shipper bag that does not require human intervention during evacuation is also needed.
An additional problem with pillow-type shipper bags is that they generally lack a filling conduit or snout that would enhance ease of filling the bags. Typically, pillow bags include fitments in their tops for filling the bags through fill hoses that can be connected to the fitments. This arrangement is meant for users who can pump bulk material into the bag through the fill hoses. However, many users either do not want or cannot pump their bulk material and instead pour their bulk material into bags, such as open-top pillow bags and fitted bags equipped with snouts. Open-top pillow bags tend to be more difficult to close than snout-equipped fitted bags and are more susceptible to contamination, but snout-equipped fitted bags are more expensive than open-top pillow bags. In addition, prior attempts to incorporate snouts into pillow-type bags have failed for one reason or another. Consequently, there is a need for a new pillow-type bag that solves the problems associated with shipper bag evacuation as enumerated above and that includes a snout for easy filling of the bag.